As known, a fuel cell vehicle provided with a fuel cell system mounted thereto supplies hydrogen which is used as fuel to a fuel cell stack for generating electricity to drive an electric motor which drives the vehicle. In this case, the fuel cell system is an electric power system which does not convert chemical energy of the fuel to heat by combustion but directly converts electrochemical energy to electrical energy within a fuel stack.
In the fuel cell system, high purity hydrogen is supplied to a fuel pole (anode) of the fuel cell from a hydrogen storage tank, and atmospheric air is supplied to an air pole (cathode) of the fuel cell by using an air supply unit, such as an air blower, during operation.
According to the related art, the hydrogen supplied to the fuel cell stack is separated into a hydrogen ion and an electron by catalyst at the fuel pole (anode), and the hydrogen ion separated thus passes through a polymer electrolyte membrane to the air pole (cathode) such that oxygen supplied to the air pole couples to the electron which comes to the air pole through an external lead line to generate the electrical energy while producing water. A membrane electrode assembly (MEA) of the fuel stack needs to have an appropriate amount of moisture maintained thereon, and a humidifier mounted to each of a fuel gas circulating line and an air circulating line circulate the stack to operate the stack.
In order to circulate the fuel gas in the fuel system, an ejector may be used. In this case, liquid state condensed water contained in the circulating fuel gas can be supplied to the stack directly, causing drops of the condensed water to block a portion of a channel of the stack. Thus, if the portion of the channel of the stack is blocked, a fuel gas supply rate to the portion of channel is reduced, and the entire stack can be deteriorated. Consequently, there have been ceaseless researches for removing the moisture being supplied to the stack.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the disclosure, and therefore, it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.